Electric lamp socket



Aug. 25, 1931. E. c. WHI'I "1 ELECTRIC LAMP SOCKET Filed May 14, 1925 I mess OANTELO wm'mor mw YORK, 11.1., mm on or cam-num To a. rmwroir rrsnm' or rmsnsnrnm, rmmsnvmn .ters Patent ELECTRIC mm SOCKET a lication w m 14,

My invention relates to the construction of electric sockets, havin' means wholly or partially self-contained or makingand breaking the circuit between one or both of the lamp contacts and the binding screws to which the supply wires are attached. 'In 111 copending application, Ser. No. 28,377, led May 6th, 1925, upon which Let- No. 1,727,148, issued September 3rd, 1929, I described. the method of constructing a keyless socket for many advantageous purposes therein described. The objects of my present invention are to furnish a socket retaining as many as possible of the same advantages and havin the additional advantage of a self-containe switch control such as is customarily provided in what are known as key sockets, push button sockets, pull chain sockets and the like. A further object of my present invention is to provide a new style of self-contained socket control in an improved manner, the many advantages of which will appear from the following description.

In the accompanying drawings, Fig. 1 is a top view of the socket body, Fig. 2 is a side view of the same and Fig. 3 is a bottom view of the same; Fig. 4 is a cross-section of the socket body on the line A-A; Fig. 5 is a cross-section of the socket body on the line BB; Fig. 6 is an edge view of the side contact member and Fig. 7 is a front view of the same; Fig. 8 is an edge 7 ,view of the center contact member and Fig.

9 is a front view of the same; Fig. 10 is a cross-section of the socket body on the line AA showing the side contact member and center contact member assembled therewith;

Fig. 11 is a top view of the socket cap; Fig.

12 is a cross-section of the socket cap on the line 0-0; Fig. 13 is'a cross-section of the socket cap on the line DD; Fig. 14 is a top view of one of the binding screw contacts and Fig. 15 is an edge view of the same; Fig. 16 is a cross-section of the socket cap on the line 0-0 with contact members and binding screws asembled therewith and supply wires connected thereto; Fig. 17 is a side elevation of the same parts as shown in Fig. 16 but with the socket cap turned 1985. lerial Io. 30,28}.

socket cap on the line 0-0 assembled together with an electric lamp'.(show'n' inside elevation) inserted in the socket; Fig. 21

is a horizontal section through the socket body and socket cap on the'line EE'with thesupply wires removed and Fig. 22 is a similar view after the socket body'. has been rotated with respect to the cap.

In carrying out my lnventlon accordi n to the illlustrated embodiment thereof,

provide a socketbody 1 formed of moulded insulating material and having internal threads 2 adapted to engage the threads of a lamp screw-shell. The interior of the socket body is partially closed by a diaphragm or floor 3 having a central circular recess 4 in the center of which is a circular hole 5 leave ing a shoulder 6. On opposite sides of the socket cap are two internal vertical grooves 7 and 8 which interrupt the threads 2 and which are continued as holes through the edge of the diaphragm and 'as grooves on the other side of the diaphragm so as to make continuouschannels from one end to the other of the socket body. The width ofthe said holes through the edge of the diaphr m is the same as that of the grooves in the t readed end of the socket body but on the other side of the diaphra m the grooves are made wider and are num ered 9 and 10 respectively. The lower inside edge of the socket body has two internal rabbets 11 and 12 for the purpose of accommodating 'lugs 13 and 14 which are formed on the socket cap in order to limit the rotation thereof with respect to the socket body.

'The side contact member 15 is formed of resilient conducting material, oneend being enlarged to form. a shoulder 16 and switch contact surface 17 and the other end being curved lengthwise as illustrated in Figs. 6 and 7. The narrow end of the member 15 is inserted from the bottom of the socket body through the communicating hole into the ove 7, it being understood that the memer is of spring material and the curved portion will flatten out sufficiently to permit of inserting it in this way. The narrow part of the member fits loosely into the groove 7 and theportion 17 thereof (its tightly into the lower portion 9 of the same groove. Consequently the shoulder 16 will seat against the shoulder 18 at the bottom level of the floor and the side contact member 15 will then occupy the position relative to the socket body which is illustrated in the cross-sectional view Fig. 10.

The contact member 19 is formed of slightly resilient conducting material, the lower rtion having a shoulder 20 and switch contact surface 21, and is formed with a crease 22 at the point where it is to bend when assembled. The contact member 19 is inserted from the bottom of the socket body through the communicating hole into the groove 8, after which the upper portion is bent over at the crease 22 so that it occupies the assembled posit-ion illustrated in Fig. 10.

The socket cap 23 is also formed of moulded insulating material with threaded inserts 24 and 25 to accommodate binding screws 26 and 27 respectively, and a central threaded insert 28 to accommodate the retainim: screw 29. The insert 28 is located in a raised central boss 30 which provides a bearing surface for the washer 31 used under the retaining screw 29 so that in the completel assembled relation illustrated in Fig. 20, t e washer 31 will hold the socket body 1 in close vertical engagement with the socket cap 23, but without exerting any ressure against the shoulder 6 oi. the socket ody.

The diameter of the socket cap above the flange 32 is such as to fit closely but rotatably into the lower portion of the socket body as illustrated in Figs. 20 and 21, so that the axes of the socket body 1 and the socket cap 23 will substantially coincidewhen assembled. The vertical distance between the lower edge 33 and the shoulder 6 of the socket body 1, is very slightly less than the vertical distance between the shoulder 34 and the top of the boss 30, so that it will be seen that the socket body and socket cap will be held in vertical and axial adjustment by the retaining screw 29 and washer 31. They can, however, only be assembled in the relative posit-ions in which the lugs 13 and 14 are positioned in the rabbets 11 and 12.

The inserts 24 and 25 are located in the bottom of recesses 35 and 36 which are shaped to receive two switch contact members 37 and which communicate with outside vertical groovcs 39 and 39 to accom modate the ends 40 of the members 37. The recesses 35 and 36 also conn'nnniratc with contacts 37 are made of resilient conducting material and have holes 44 for the passage of the bindingscrews 26 and 27, which serve to hold the supply wires 45and 46 in electrical contact with the members 37 and also to hold the members 37 in fixed assembled position .in the grooves 38 and 39.

The complete assembly and wiring of the socket may be carried outby first assembling the contacts 15 and 19 in the socket body as illustrated in Fig. 10, then connecting the wires to the binding screws on the socket cap as illustrated in Fig. 16, then placing the socket body in position over the socket cap, inserting washer 31 andscrew 29 and drawing the screw 29 up tight. For this purpose, contact 19 may remain unbent u to this point or if it has already been Bent over, it may be bent back into the position shown in dotted lines in Fig. 10 in order to give convenient access with a screw driver to the screw 29, after which the contact should be bent down as far as it will go, when it will ordinaril spring back to the apw'oximate position s own in Fig. 10.

' hen a lamp is inserted in the socket, the contact 15 will be flattened out by the lamp screw-shell along the groove 7 as illustrated in Fig. 20, and the contact 19 will be pressed down by the center contact of the lamp as shown in Fig. 20. In this position the contact 19 may bear against the screw 29. This will do no harm as it will be seen that screw 29, washer 31 and insert 28 are electrically insulated from all other contacts. However, the contact 19 rotates with the socket body and the screw 29 is made tight with the socket cap so that rotation of the body with respect to the cap moves the contact 19 rotatably with respect to the screw 29, with the result that the tighter the lamp is screwed into the socket, the more difiicult will it be to rotate the socket body with respect to the cap. This may serve a very useful purpose under many (301lditions. If preferred, this condition may be avoided entirely by using a thinner washer 31 and lengthening the contact member 19 enough so that it will bear on the opposite side of the recess 4.

Attention is now called to Fig. 21 which is a horizontal cross-section of the assembled socket on the line EE and which shows the relation of parts when the side contact 16 and center contact 19 are connected electrically to the binding screws 26 and 27 respectively through the two switch c0ntact members 37 which bear against the contact surfaces 17 and 21 respectively. Assuming the socket cap to be fixed in position, the socket body may be turned to the right until the lugs 13 and 14 reach the opposite ends of the rabbets 11 and12, when the relative position of the parts will be that shown in Flg. 22. It will then be seen. that the two switch contacts 37 have moved out of contact with the ends 17 and 21 of the contacts 15 and 19 respectively, and are separated therefrom, not merely by an air space which might permit arcing under such conditions, ut .by the intervention of moulded insulating material in close contact. This does away with the necessity for a snap or spring action in separating the contacts to prevent arcin because the ordinary and convenient rate 0 rotation of the socket body with respect to the socket cap b anyone desiring to turn a light on or o provides a practically instantaneous interposition of insulatmg material between the contacts as soon asthey are separated, which promptly smothers any tendency to form an are. It will also be seen'that the frictional contact of the v'arious parts will operate to keep the contact surfaces always clean.

In order to provide the best results, the

' lower ends 17 and 21 of the contacts 15 and 19 are curved to conform with the internal diameter of the socket body and the ends 40 of the two contacts 37 are also formed with a curved section to conform with the outside diameter of the socket cap as illustrated clearly in Figs. 21 and 22. The ends 40 of the contacts 37 occupy the position shown in Fig. 16 before the socket body and socket cap are assembled. Upon complete assembly, these ends are pressed into the grooves 38 and 39 by the pressure of the contact surfaces 17v and 21 against which they exert a suflicient pressure to insure good electrical contact.

The socket above described, is whatwould be called a double pole socket because both the side and center contacts are disconnected from the binding screws when the socket body is rotated as described. In the best practice it is customary to always open the circuit of the side contact, if only one side is broken. If it is desired to construct the socket so as not to break the center contact, this may be easily accomplished by widening the end 21 of the contact 19 and correspondingly widening the lower groove 10 so that one of the contacts 37 will always remain in contact therewith, when the parts are rotated. It is preferable, however, to interrupt the circuit to both contacts and it is one of the advantages of the construction here illustrated that this may be done so simply and effectively. 7

The lugs 13 and 14 may be omitted from the construction of the socket cap if desired,

in which case the rabbets 11 and 12 may be omitted from the socket body. It will then be possible to turn the socket body freely in either direction with respect to the socket cap and the socket will be switched on socket for certain special whenever the contact surfaces 40 are opposite the contact surfaces 17 and 21 respectively. Such modified construction has its advantages as it permits the use of the urposes for which it is desired to switch ights on and off by constant rotation by the socket body with respect to the cap.

Another important advantage of the socket construction herein described is that either the socket body, or the socket cap, or both may be moulded integrally with important parts of lighting fixtures or electrical appliances, so that the rotation of the socket body with respect to the socket cap may be actuated by corresponding rotation of said important parts of lighting fixtures and appliances without the necessityfor having actual access to the socket itself for this purpose.

It will be understood that the method of constructing a switched socket herein described may be varied considerably in detail without sacrificing the improvement resulting from theme of moulded insulating material and conducting members in the general relation described. My invention, therefore, includes all devices in which the construction and assembly of. parts include what I claim as new, which is:

1. An electric lamp socket including in combination a socket body formed of insulating material, a lamp receiving chamber in the socket body, apartition of insulating material forming a bottom closure for the lamp receiving chamber, an openingin the partition near the side of the chamber, a contact member adapted to be inserted through the opening and having an enlarged end adapted to seat against one sideof the partition, the other end of the'contact member be ng adapted to engage the screw-shell contact of a lamp base, a socket cap formed of insulating material and having a supply contact carried thereby and means for attaching the socket cap to the socket body the socket cap being adapted to engage the enlarged end of the contact member so as to retain the contact member in position and to provide a working con-' tact between the contact member and the supply contact.

2. An electric lam socket including in combination a socket ody of moulded insulating material, a lam receiving chamber in one end of the soc et'body, a cap receiving chamber in the other end of the socket body, a partition of insulating material between the two chambers, a slot formed in the side of one chamber and extended to form an opening through the partition and a communicating slot in the side. of the other chamber, a socket cap partially housed by the cap receiving chamber, suppl contacts carried by the socket cap, means or attach-' ing the socket cap rotatably to the socket body, a contact member positioned in the slot in the cap receiving chamber and extending through the opening in the partition into the slot in the lamp receiving chamber, one end of the cont-act member being adapted to engage the screw-shell of a lamp base, the other end of the contact member being adapted to engage the supply contact, the contact member being held in assembled relation with the socket body by the socket cap.

An electric lamp socket including a lamp receiving member formed of insulating material, a cap member formed of insulating material, means for attaching the cap member tosaid lamp receiving member so as to be rotatable about the longitudinal axis thereof, means to limit the rotative movement of one member relative to the other, the said members being formed to provide substantially cylindrical working surfaces between the two members, longitudinal recesses in the said working surface of the lamp receiving member, contact members in the said recesses, supplemental registering recesses in the worklng surface of the second member supply contact members in the latter recesses, all of the said parts being arranged so as to make and break contact between the contact member and the supply contact when the lamp receiving member is rotated with respect to the cap member, and means to prevent axial separation of one member from the other.

4. An electric lamp socket comprising a socket body having a fixed partition intermediate its ends, said partition formin a bottom closure for the lamp receiving en of said body, a socket cap rotatably engaged with the opposite end of said socket body, said cap having a central interior stud, said partition having an axial opening to receive said stud, means interengaged with said stud and partition to prevent longitudinal separation of said cap from said body while permitting relative axial movement, means to limit rotative movement of said cap relative to said body, main contact devices disposed at the interior surfaces of and in fixed relation to said lamp receiving end of said body, said main contact devices extending through said partition toward said socket cap, supply contacts carried by said socket cap having resilient free ends respectively movable into and out of frictional engagement with the adjacent portions of the respective main contact devices upon relative rotative movement of said cap and bod Signed at New York, N. Y., on this 11th day of May, 1925.

ERNEST CANTELO WHITE. 

